National health care reform efforts are resulting in changing systems of health care delivery including managed care and capitated reimbursement. Accompanying these changes is a critical need to know the health problems of patient groups, provider time needed to care for specific problems, what interventions yield optimal patient outcomes and if provider interventions could be more efficient and/or cost effective. The purpose of this study is to document patient problems and accompanying practice functions of advanced practice nurses (APNs) during transitional care (hospital discharge planning & home follow-up care) delivered to 5 groups of high risk, high cost, high volume patients. The 5 study groups include very low birthweight infants, women with cesarean birth, high risk pregnancies, and hysterectomy surgery, and elders with cardiac medical and surgical diagnoses. The second study purpose is to being establishing links between patient problems, APN practice functions, nurse time consumed, patient outcomes and health care costs. Data will compare the effects of the APN interventions on health care costs and satisfaction with care in intervention patients with and without morbidity compared to routine care patients with and without morbidity. The study is a secondary analysis of data from 5 randomized trials (N=675; intervention=333; control=342). Hand written comprehensive patient log data will be analyzed, using the Omaha system, to document patient problems and APN practice functions. Patient outcome variables, common across groups and with sufficient variance, will be used to link outcomes with patient problems, APN practices, nurse time consumed and health care costs. Outcome variables include morbidity, satisfaction with care, negative affect, and functional status. Methods of data analysis include both parametric and non parametric tests to examine differences within each study intervention group taken separately, and meta-analytic procedures to examine combined data from all 5 studies.